A bearingless disposable centrifugal blood pump will be developed in the proposed project, together with a compact, inexpensive driver and controller. The rotor of the pump will be suspended by a combination of magnetic and fluid forces so that it is washed on all surfaces by moving blood. The elimination of bearings and shaft seals removes sources of local heating and blood stagnation, making such a pump safer and more reliable for short to medium term use, and applicable for post-cardiotomy support and bridge to transplantation. The proposed drive and suspension mechanism, consisting of permanent magnets and copper windings, is simple and inexpensive to manufacture. The driving coils will be able to actuate existing pumps, and have no moving parts, an improvement over those currently available. The Phase I program will focus on the drive mechanism and positional stability of the bearingless disposable pump. Its goal will be to demonstrate reliable suspension of the pump rotor, synergistically using hydrodynamic, permanent magnet, and feedback controlled electromagnetic forces. The results of the Phase I studies will be used in Phase II to build and test blood-compatible prototypes of the pump, and to investigate options for manufacturing it in larger quantities. PROPOSED COMMERCIAL APPLICATION: The potential application of the device is in approximately 300,000 cardiac surgery cases per year in the US which require cardiopulmonary bypass. The proposed device will be particularly appropriate for use in those patients requiring circulatory support extending beyond a few hours, into the range of a few weeks. These cases number approximately 10,000 annually in the US.